A new type of small circuit breaker with bimetallic strip

Abstract

The utility model relates to a novel miniature circuit breaker of bimetallic strip constructs a reliable mechanical trip system through the cooperation of mechanical clamp assembly, push rod, bimetallic strip and other components, when the bimetallic strip is bent and deformed due to overload current, will push the push rod action, and then triggers the trip mechanism of mechanical clamp assembly, makes the moving contact and static contact separate rapidly, cuts off the circuit, and the bimetallic strip has two bending structures, utilizes the resultant force of bimetallic strip in two directions, makes it produce more deflection, compared with the bimetallic strip of only one angle in the prior art, can push the lock catch structure to produce greater displacement, thereby makes the product when the circuit appears overload and other abnormal conditions can trip faster, cuts off the circuit in time, effectively protects the electrical equipment and circuit safety, and because the two bending structures of bimetallic strip make it more uniform and stable in the stress deformation process, reduces the unstable factors possibly brought by single angle deformation.

Description

Technical Field

[0001] This utility model relates to the field of miniature circuit breaker technology, and in particular to a novel bimetallic miniature circuit breaker. Background Technology

[0002] In the field of electrical safety, miniature circuit breakers (MCBs) are core devices ensuring the safe operation of circuits. The performance and design of their core component, the bimetallic strip, directly determine the tripping characteristics and reliability of the circuit breaker. Currently, most miniature circuit breakers on the market use traditional bimetallic strips with only one bending angle. Their working principle is based on the fact that the bimetallic strip bends and deforms due to the difference in thermal expansion coefficients of the two metals when heated. The angle change caused by the normal deflection pushes the latch to unlock, thus achieving tripping. However, this single-angle design has obvious limitations. On the one hand, when the bimetallic strip with a single angle pushes the latch, the displacement and force are limited. In the face of severe overload or emergency situations requiring rapid circuit disconnection, it may not be able to trigger the tripping mechanism in time, increasing the risk of electrical accidents. On the other hand, the stress distribution is uneven when it deforms, which easily leads to local stress concentration, accelerating fatigue damage, reducing service life and performance stability. Moreover, the uneven deformation causes the bimetallic strip to have large performance differences under different ambient temperatures and operating conditions, resulting in unstable tripping characteristics of the circuit breaker, making it difficult to meet increasingly stringent electrical safety standards. Utility Model Content

[0003] In view of this, the purpose of this utility model is to provide a new type of miniature circuit breaker with bimetallic strip that has reliable tripping performance, can quickly respond to circuit abnormalities, and effectively protect electrical equipment and circuit safety.

[0004] To achieve the above objectives, this utility model employs a novel bimetallic strip miniature circuit breaker, comprising a housing. Within the housing are disposed a first moving connection assembly, a second moving connection assembly, two stationary connection assemblies, and a mechanical clamping assembly. The first and second moving connection assemblies are both located at one end of the mechanical clamping assembly, and the two stationary connection assemblies are both located at the other end of the mechanical clamping assembly. A first push rod and a second push rod are respectively provided on both sides of the mechanical clamping assembly. Each of the first and second push rods has a moving contact at its end near the corresponding stationary connection assembly. Each stationary connection assembly has a stationary connection. The plate has a stationary contact corresponding to the corresponding moving contact position. The first push rod has a bimetallic strip installed at the end near the first moving connection assembly. The bimetallic strip has two bending structures. The first moving connection assembly has a wire for transmitting current at the position corresponding to the bimetallic strip. The first moving connection assembly has a first moving connection plate inside, and the second moving connection assembly has a second moving connection plate inside. One end of the wire is connected to the first moving connection plate inside the first moving connection assembly, and the other end is connected to the bimetallic strip. The end of the second push rod is connected to the second moving connection plate inside the second moving connection assembly by a bolt.

[0005] Compared with existing technologies, the advantages of the above structure are as follows: By working together with components such as the mechanical clamp assembly, push rod, and bimetallic strip, a reliable mechanical tripping system is constructed. When the bimetallic strip bends and deforms due to overload current, it pushes the push rod to move, thereby triggering the tripping mechanism of the mechanical clamp assembly, causing the moving contact and stationary contact to separate quickly and cut off the circuit. The bimetallic strip has two bending structures, and by utilizing the combined force of the bimetallic strip in two directions, it can generate more deflection. Compared with the bimetallic strip in existing technologies with only one angle, it can push the locking structure to generate greater displacement, so that the product can trip faster when the circuit is overloaded or other abnormal, cut off the circuit in time, and effectively protect electrical equipment and circuit safety. Moreover, due to the two bending structures of the bimetallic strip, it is more uniform and stable during the deformation process under force, reducing the instability factors that may be caused by deformation at a single angle.

[0006] This utility model is further configured as a mechanical clamping assembly including clamping arms, clamping locking plates, operating handles, and supporting guide shafts. The clamping arms are fixedly installed inside the housing. The clamping locking plates are located at one end of the clamping arms near the stationary wiring assembly. The clamping arms are provided with through holes for the supporting guide shaft to pass through. The supporting guide shaft passes through the through holes of the clamping arms. The operating handle is rotatably mounted on the supporting guide shaft and extends to the outside of the housing through a handle slot opened on the housing. A first torsion spring is wound around the supporting guide shaft and is located between the clamping arms. By fixing the clamping arms inside the housing, a stable foundation support is provided for the entire mechanical clamping assembly, ensuring that it will not easily shake or shift due to external forces during operation. The clamping arms are provided with through holes for the support guide shaft to pass through, providing precise guidance for the movement of the clamping arms and other connected components. The operating handle is rotatably mounted on the support guide shaft, allowing the operator to perform the disengagement or closure operation of the mechanical clamping assembly with a simple handle rotation action. The operation is convenient and quick, reducing the difficulty of operation and labor intensity.

[0007] This utility model is further configured with a connecting rod opening at the end of the operating handle extending between the clamping arms. A connecting rod is inserted into the connecting rod opening, and the other end of the connecting rod is connected to a locking block located between the clamping arms and below the operating handle. The clamping arms have through-hole grooves corresponding to the connecting rod, and the locking block has through-hole openings corresponding to the connecting rod. By opening a connecting rod opening at the end of the operating handle and inserting the connecting rod, with the other end of the connecting rod connected to the locking block below the operating handle, a linkage structure is constructed. When the operating handle is rotated, the connecting rod moves accordingly within the connecting rod opening, causing the locking block to move synchronously. The through-hole grooves on the clamping arms corresponding to the connecting rod provide reasonable space and guidance for the movement of the connecting rod.

[0008] This utility model is further configured such that the clamping arms are connected to a locking buckle via a shaft at one end near the moving connection assembly. A second torsion spring is wound around the locking buckle. A protrusion is provided at the bottom of the clamping plate, and a spring is sleeved on the protrusion. One end of the spring abuts against the protrusion, and the other end abuts against the housing. The locking buckle, which is shaft-connected to the clamping arms near the moving connection assembly, provides a key support point and limiting reference for the entire mechanical structure. The torsion spring wound around the locking buckle provides an elastic reset function for the mechanical clamping assembly. When the operating handle drives the relevant structure to rotate or displace, the torsion spring will elastically deform and store energy. The spring sleeved on the protrusion at the bottom of the clamping plate, with its two ends abutting against the protrusion and the housing respectively, provides stable elastic support for the movement of the clamping plate.

[0009] This utility model is further configured such that a first push rod and a second push rod are respectively engaged on both sides of the clamp locking plate, and both the first and second push rods are multi-layered composite structures. By engaging the first and second push rods on both sides of the clamp locking plate, this engagement method significantly increases the contact area and connection strength between the push rods and the clamp locking plate compared to traditional single-point or single-sided connections. The multi-layered composite structure of the push rods allows for full utilization of the advantages of each layer of material, achieving an optimized combination of mechanical properties. Attached Figure Description

[0010] Figure 1 This is a structural schematic diagram of an embodiment of the present utility model.

[0011] Figure 2 This is a schematic diagram of the internal structure of an embodiment of the present utility model.

[0012] Figure 3 This is a top view of the internal structure of an embodiment of the present utility model.

[0013] Figure 4 This is a schematic diagram of the bimetallic strip structure according to an embodiment of the present invention.

[0014] Figure 5 This is a side view of the internal structure of an embodiment of the present utility model.

[0015] Figure 6 This is an exploded view of the mechanical clamp assembly according to an embodiment of the present invention. Detailed Implementation

[0016] like Figures 1-6As shown, an embodiment of this utility model provides a novel miniature circuit breaker with a bimetallic strip, including a housing 1. The housing 1 contains a first moving connection assembly 21, a second moving connection assembly 22, two stationary connection assemblies 3, and a mechanical clamp assembly 4. The first moving connection assembly 21 and the second moving connection assembly 22 are both located at one end of the mechanical clamp assembly 4, and the two stationary connection assemblies 3 are both located at the other end of the mechanical clamp assembly 4. A first push rod 41 and a second push rod 42 are respectively provided on both sides of the mechanical clamp assembly 4. The first push rod 41 and the second push rod 42 each have a moving contact 5 near the end of the corresponding stationary connection assembly 3. Each stationary connection assembly 3 has a stationary connection plate 31, and the stationary connection plate 31 has a stationary contact 32 corresponding to the position of the moving contact 5. A bimetallic strip 6 is mounted on the end of the first push rod 41 near the first moving connection assembly 21. The bimetallic strip 6 has two bending structures, including a first bend 61 and a second bend 62, which allows it to deform more precisely and quickly when heated. The bimetallic strip 6 pushes the screw on the latch 49, causing the latch 49 to deflect to the right. The latch 49 unlocks from the locking block 48, disconnecting the product contacts and achieving rapid circuit disconnection. The bimetallic strip 6 has two bending structures. The first moving connection assembly 21 is provided with a wire 20 for transmitting current at the position corresponding to the bimetallic strip 6. The first moving connection assembly 21 is provided with a first moving connection plate 211, and the second moving connection assembly 22 is provided with a second moving connection plate 221. One end of the wire 20 is connected to the first moving connection plate 211 in the first moving connection assembly 21, and the other end is connected to the bimetallic strip 6. The end of the second push rod 42 is connected to the second moving connection plate 221 in the second moving connection assembly 22 by a bolt.

[0017] The mechanical clamping assembly 4 includes clamping arms 43, clamping locking plate 44, operating handle 45, and supporting guide shaft 46. The clamping arms 43 are fixed inside the housing 1. The clamping locking plate 44 is located at one end of the clamping arms 43 near the stationary wiring assembly 3. The clamping arms 43 are provided with through holes for the supporting guide shaft 46 to pass through. The supporting guide shaft 46 passes through the through holes. The operating handle 45 is rotatably mounted on the supporting guide shaft 46 and extends to the outside of the housing 1 through the handle groove on the housing 1. A first torsion spring 47 located between the clamping arms 43 is wound around the supporting guide shaft 46.

[0018] The operating handle 45 extends to the end between the clamping arms 43 and has a connecting rod opening. A connecting rod 451 is inserted into the connecting rod opening. The other end of the connecting rod 451 is engaged with a locking block 48 located between the clamping arms 43 and below the operating handle 45. The clamping arms 43 have a waist-shaped groove corresponding to the connecting rod 451, and the locking block 48 has a connection opening corresponding to the connecting rod 451. The clamping arms 43 have a locking buckle 49 connected to the end near the moving connection assembly 2 via a shaft. A second torsion spring 491 is wound around the buckle. The clamping locking plate 4 4. A protrusion 441 is provided at the bottom, and a spring 442 is sleeved on the protrusion 441. One end of the spring 442 abuts against the protrusion 441, and the other end abuts against the housing 1. The first push rod 41 and the second push rod 42 are respectively engaged on both sides of the clamp locking plate 44, and both adopt a four-layer composite structure. This four-layer structure is designed according to the functional requirements of the circuit breaker. The materials of each layer work together to give the push rod good conductivity, mechanical strength, insulation, corrosion resistance, wear resistance and other properties, protect the internal structure and ensure reliable operation of the circuit breaker.

[0019] Of course, in addition to the above embodiments, this utility model may have other various embodiments. Without departing from the essential technical solution of this utility model, those skilled in the art can make various corresponding changes and modifications based on this utility model, and these changes or modifications are equivalent to the technical solution in this patent. Therefore, these corresponding changes and modifications should all fall within the protection scope of the appended claims of this utility model.

Claims

1. A novel bimetallic strip miniature circuit breaker, characterized in that: The device includes a housing, within which are disposed a first movable wire assembly, a second movable wire assembly, two stationary wire assemblies, and a mechanical clamp assembly. The first and second movable wire assemblies are each disposed at one end of the mechanical clamp assembly, and the two stationary wire assemblies are each disposed at the other end of the mechanical clamp assembly. A first push rod and a second push rod are respectively disposed on both sides of the mechanical clamp assembly. Each of the first and second push rods has a movable contact at its end near the corresponding stationary wire assembly. Each stationary wire assembly has a stationary wire plate, with a stationary contact corresponding to the movable contact position. A bimetallic strip with two bends is mounted on the end of the first push rod near the first movable wire assembly. A wire for transmitting current is disposed on the first movable wire assembly corresponding to the bimetallic strip. A first movable wire plate is disposed within the first movable wire assembly, and a second movable wire plate is disposed within the second movable wire assembly. One end of the wire is connected to the first movable wire plate within the first movable wire assembly, and the other end is connected to the bimetallic strip. The end of the second push rod is connected to the second movable wire plate within the second movable wire assembly via a bolt.

2. The novel bimetallic strip miniature circuit breaker according to claim 1, characterized in that: The mechanical clamping assembly includes clamping arms, a clamping locking plate, an operating handle, and a supporting guide shaft. The clamping arms are fixedly installed inside the housing. The clamping locking plate is located at one end of the clamping arms near the stationary wiring assembly. The clamping arms have through holes through which the supporting guide shaft passes. The supporting guide shaft passes through the through holes of the clamping arms. The operating handle is rotatably mounted on the supporting guide shaft and extends to the outside of the housing through a handle slot. A first torsion spring is wound around the supporting guide shaft and is located between the clamping arms.

3. The novel bimetallic strip miniature circuit breaker according to claim 2, characterized in that: The operating handle extends to the end between the clamping arms and has a connecting rod opening. A connecting rod is inserted into the connecting rod opening. The other end of the connecting rod is connected to a locking block located between the clamping arms and below the operating handle. The clamping arms have a through-connected waist-shaped groove corresponding to the connecting rod, and the locking block has a through-connected connection opening corresponding to the connecting rod.

4. The novel bimetallic strip miniature circuit breaker according to claim 2 or 3, characterized in that: The clamping arms are connected to a locking buckle via a shaft at one end near the moving connection assembly. A second torsion spring is wound around the locking buckle. A protrusion is provided at the bottom of the clamp locking plate. A spring is sleeved on the protrusion. One end of the spring abuts against the protrusion, and the other end abuts against the housing.

5. The novel bimetallic strip miniature circuit breaker according to claim 4, characterized in that: The first push rod and the second push rod are respectively engaged on both sides of the clamp locking plate, and both the first push rod and the second push rod are configured with a multi-layer composite structure.

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